Heyrman I was a campsite and stone tool workshop occupied almost continuously from Paleoindian to Historic Euroamerican times on a long, narrow, saddle-shaped sand ridge parallel to the original WIS 57, part of the same ancient lake terrace system as the nearby Fabry Creek (Boss Tavern) site. First identified in 1994, and investigated through the 2005 field season, the site yielded more than 350 archaeological features and about 12,500 artifacts, including evidence of very early human occupation dating to more than 12,000 years ago. Its Paleoindian deposit, found 170 cm below the surface, contained more than 1,500 pieces of chipped stone from the manufacture of a Paleoindian tool, with associated organic materials radiocarbon dated to between 10,860 and 9980 B.C.; together with Fabry Creek, it shows an early and continued Paleoindian presence on the Door Peninsula. Archaic materials from 40 to 60 cm below the surface included chipped stone and ground stone tools such as knives, projectile points, hammers, and grinding stones. The Middle Woodland component included North Bay type projectile points, more than 5,000 pieces of chipped stone, and three small pieces of grit-tempered pottery. Late Woodland artifacts included Heins Creek pottery and small triangular arrow points typical of Late Woodland groups on the Door Peninsula, and Heins Creek people probably camped there between A.D. 700 and A.D. 1000.